Problem: What do the following two equations represent? $-5x+5y = 5$ $-10x+10y = 0$
Answer: Putting the first equation in $y = mx + b$ form gives: $-5x+5y = 5$ $5y = 5x+5$ $y = 1x + 1$ Putting the second equation in $y = mx + b$ form gives: $-10x+10y = 0$ $10y = 10x$ $y = 1x + 0$ The slopes are equal, and the y-intercepts are different, so the lines are parallel.